Dawn Olivieri, <i>Heroes</i> Dawn Olivieri, Heroes

Naturally, Dawn Olivieri was bummed when she found out Lydia, her character on Heroes, was being killed off.

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But she also saw the bright side: Lydia's death could blow the lid off twisted carnival leader Samuel's master plan. "My death was a chance for the audience to see just how far he's willing to go," Olivieri tells TVGuide.com. Lydia — a tattooed empath who can see into any person's soul — was the second member of the carnival to fall victim to Samuel (Robert Knepper

), who earlier in the season killed his own brother and set forth with his egomaniacal plot.This time around, Samuel had one of his henchman open fire on the carnival while telling his "family" that they were under attack from the outside world. Lydia was caught in the crossfire, but played perfectly into Samuel's hands. His hope that the hysteria would eventually help him regain control and the trust of his people seemed to work, but Olivieri says Samuel won't be able to sustain the lie.

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"He's pushing it, and he's getting really close to the fire with all the things he's doing," she says. "I think the closer he gets, the more extreme his actions have to be, and eventually that just all implodes on itself. He's sinking cities, and he's killing the people that are close to him. It becomes too much eventually; it's catching up with him."The most likely candidate to play spoiler to Samuel's schemes: Claire (Hayden Panettiere), who returned to the carnival just before Lydia was gunned down. Although Lydia didn't get a chance to tell Claire everything she knew, Olivieri says the indestructible cheerleader will spring into action."I think Lydia gave Claire the insight that the carnival wasn't this roving band of lunatics," Olivieri says. "She was able to convey to Claire what it really meant to the people that were there and that they wanted help. Samuel is not on their side. If anything, that gives Claire incentive to get her father [Jack Coleman] to help."

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Even though Lydia's dead, Olivieri knows the secrets that lie ahead in the finale. Of course, she's not talking, but she says fans will be pleased with the finale. "We know how these things work," she says. "Somebody's got to figure something out. The writers did a good job on the ending. There's a few twists that you don't see coming that I personally loved, and it made me crazy to know what happens next."Heroes' penultimate Season 4 episode airs Monday at 9/8c on NBC.